Numbers can include one decimal point or a comma for entering fractional portions.
Because of rounding, the preview text and the calendar may differ by 1/10th of a minute—this does not significantly affect any of the times calculated.

Footnotes:

1. The fields latitude and longitude "as Decimal" are the ones used to create the calendar.
Latitudes of 89.9 and higher will be rounded up to 90.

You can also use the preview area, "as Degrees Minutes Dir", to enter your coordinates.
Separate the numbers with a space and for "Dir" use N, S, E or W.

2. The time zone setting,
will adjust time offsets (zones) and DST rules for locations that changed either during their existence,
e.g. Cancún, Mexico changed from Central to Eastern time on 1 Feb 2015; and, The Bahamas
has used both North American and their own DST rules. This will override the time offset and dst rule settings.

3. To enter a half-hour time zone use a .5, for example -3.5 for Newfoundland, Canada.

4. On the calendar, latitude and longitude will be shown with the notation "not for navigational purposes".
Please see the Accuracy page for the reason why.